New Magnitude Proxy for Earthquake Early Warning Based on Initial Time Series and Frequency

作者：Wang, Yanwei; Li, Xiaojun; Li, Li; Wang, Zifa^*; Lan, Jingyan

来源：SEISMOLOGICAL RESEARCH LETTERS, 2022, 93(1): 216-225.

DOI：10.1785/0220210106

• RAPID ESTIMATION
• P-WAVE
• SYSTEM

A new characteristic parameter S-d tau is proposed to improve the performance of magnitude estimation in earthquake early warning (EEW). S-d tau is the product of summation of absolute displacement multiplied by the maximum predominant period (tau(p)(max)) for the first arriving seconds of a seismic wave. About 30,725 underground records at borehole stations for 3645 earthquakes with magnitude between 4.0 and 9.0 from the Japanese KiK-net were used to compare the magnitude proxy performance based on the proposed S-d tau with that based on either tau(p)(max) or peak displacement P-d. The comparison results show that for a magnitude between 4.0 and 7.3, S-d tau has a better correlation with magnitude and higher estimated accuracy than either tau(P)(max) or P-d. Hypocentral distance is not required when using S-d tau, but it can be used to further improve the accuracy of magnitude estimate. These results confirm that S-d tau can significantly improve the accuracy and timeliness of continuous magnitude estimation in an EEW system.

• 单位
  桂林理工大学; 北京工业大学